CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Operating revenues	$ 3,283,499	$ 3,289,978	$ 2,734,372
Operating expenses:
Salaries, wages and benefits	1,072,558	1,020,609	895,012
Fuel	345,001	437,299	245,866
Supplies and maintenance	256,494	253,096	206,701
Taxes and licenses	102,684	97,929	96,095
Insurance and claims	138,516	147,365	98,658
Depreciation and amortization	299,509	279,923	267,700
Rent and purchased transportation	886,284	777,464	641,159
Communications and utilities	18,480	15,856	13,460
Other	(12,443)	(62,639)	(39,425)
Total operating expenses	3,107,083	2,966,902	2,425,226
Operating income	176,416	323,076	309,146
Other expense (income):
Interest expense	33,535	11,828	4,423
Interest income	(6,701)	(1,731)	(1,211)
Loss (gain) on investments in equity securities, net	278	(12,195)	(40,317)
Loss from equity method investment	1,046	0	0
Other	477	388	236
Total other expense (income)	28,635	(1,710)	(36,869)
Income before income taxes	147,781	324,786	346,015
Income tax expense	35,491	79,206	84,537
Net income	112,290	245,580	261,478
Net loss (income) attributable to noncontrolling interest	92	(4,324)	(2,426)
Net income attributable to Werner	$ 112,382	$ 241,256	$ 259,052
Earnings per share:
Basic (in dollars per share)	$ 1.77	$ 3.76	$ 3.84
Diluted (in dollars per share)	$ 1.76	$ 3.74	$ 3.82
Weighted-average common shares outstanding:
Basic (in shares)	63,374	64,125	67,434
Diluted (in shares)	63,718	64,579	67,855